An electrical battery generally consists of one or more electrochemical cells that provide for the conversion of stored chemical energy into electrical energy. Electrical batteries have taken many different forms since the first voltaic pile was invented and used by Alessandro Volta in 1800, and today they are utilized to power both household items and industrial equipment. Batteries range in size from the small cells used in hearing aids, watches, and even newer miniature batteries for medical implantation to treat neurological disorders, to large battery packs for hybrid cars. A hybrid car battery today may comprise up to 28 nickel metal hydride modules connected in series to produce a nominal voltage exceeding 200 volts.
Batteries had for many years been designed for one-time use, only to be discarded after they were unable to support continuous functioning of the unit. Early rechargeable batteries were not very robust, as they suffered from memory effect where, in nickel cadmium batteries, repeated recharging would reduce the batteries ability to be recharged to its maximum energy capacity. But today's lithium-ion cells may be recharged multiple times and last for years, which is particularly useful for units whose operations normally require standby power, such as for cell phones, personal digital assistants (PDAs), hand-held scanners, and laptop computers.
Due to the power requirements involved in wireless communications, and particularly for mobile computing, a battery pack is often utilized, where the battery pack interconnects the electrical conductivity between any number of batteries, which are preferably identical. Many units will have a custom-designed battery and battery compartment. An example of this is shown by U.S. Pat. No. 6,421,233 to Hong for “Pocket Personal Computer with Improved Battery Compartment Enclosing Structure.” Some units will merely be designed to accept ordinary rechargeable batteries, such as the “Dual Orientation Display Handheld Computer Devices” in U.S. Pat. No. 5,949,408 to Kang. The detailed disclosure in the Kang patent merely states, as to battery power and battery configuration, that “A main battery receiving area is provided by a chamber defined by a portion the hinge mechanism 25 to receive a pair of replaceable batteries” and that “A back-up battery is held by a tray 29 which is slidably received inside a chamber defined by the clamshell lid 22.”
However, none of the battery pack and battery compartment designs have thus far addressed a concern of many users and manager's of those users, which is that removal of the battery out of a unit with a Microsoft operating system, particularly Windows mobile, doesn't give the operating system enough time to shut down in an “orderly” fashion. Although axial connectors may be spring loaded in compression to provide a longer contact period, such as that shown by U.S. Pat. No. 7,626,357 to Hoffman, they insufficient to adequately address the problem.
This invention solves the problem of insufficient system shut-down time during intentional or inadvertent battery disconnection, by provides a means of giving the device enough of warning about impending shut down to close down, so as to save data and keep the unit stable for when it is turned back on. The invention disclosed herein also addresses the need for an easily removable battery pack that nonetheless remains securely attached to the product after accidental dropping, and which also resists inadvertent removal and electrical disconnection.